diff --git a/internal/archiver/tree_saver_test.go b/internal/archiver/tree_saver_test.go
index 67ef21111..053b3e249 100644
--- a/internal/archiver/tree_saver_test.go
+++ b/internal/archiver/tree_saver_test.go
@@ -11,31 +11,38 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-func newFutureBlobWithResponse() FutureBlob {
+func treeSaveHelper(ctx context.Context, t restic.BlobType, buf *Buffer) FutureBlob {
 	ch := make(chan SaveBlobResponse, 1)
 	ch <- SaveBlobResponse{
 		id:         restic.NewRandomID(),
 		known:      false,
-		length:     123,
-		sizeInRepo: 123,
+		length:     len(buf.Data),
+		sizeInRepo: len(buf.Data),
 	}
 	return FutureBlob{ch: ch}
 }
 
-func TestTreeSaver(t *testing.T) {
+func setupTreeSaver() (context.Context, context.CancelFunc, *TreeSaver, func() error) {
 	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
 	wg, ctx := errgroup.WithContext(ctx)
 
-	saveFn := func(ctx context.Context, t restic.BlobType, buf *Buffer) FutureBlob {
-		return newFutureBlobWithResponse()
-	}
 	errFn := func(snPath string, err error) error {
 		return err
 	}
 
-	b := NewTreeSaver(ctx, wg, uint(runtime.NumCPU()), saveFn, errFn)
+	b := NewTreeSaver(ctx, wg, uint(runtime.NumCPU()), treeSaveHelper, errFn)
+
+	shutdown := func() error {
+		b.TriggerShutdown()
+		return wg.Wait()
+	}
+
+	return ctx, cancel, b, shutdown
+}
+
+func TestTreeSaver(t *testing.T) {
+	ctx, cancel, b, shutdown := setupTreeSaver()
+	defer cancel()
 
 	var results []FutureNode
 
@@ -52,9 +59,7 @@ func TestTreeSaver(t *testing.T) {
 		tree.take(ctx)
 	}
 
-	b.TriggerShutdown()
-
-	err := wg.Wait()
+	err := shutdown()
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -76,20 +81,9 @@ func TestTreeSaverError(t *testing.T) {
 
 	for _, test := range tests {
 		t.Run("", func(t *testing.T) {
-			ctx, cancel := context.WithCancel(context.Background())
+			ctx, cancel, b, shutdown := setupTreeSaver()
 			defer cancel()
 
-			wg, ctx := errgroup.WithContext(ctx)
-
-			saveFn := func(ctx context.Context, tpe restic.BlobType, buf *Buffer) FutureBlob {
-				return newFutureBlobWithResponse()
-			}
-			errFn := func(snPath string, err error) error {
-				return err
-			}
-
-			b := NewTreeSaver(ctx, wg, uint(runtime.NumCPU()), saveFn, errFn)
-
 			var results []FutureNode
 
 			for i := 0; i < test.trees; i++ {
@@ -115,13 +109,10 @@ func TestTreeSaverError(t *testing.T) {
 				tree.take(ctx)
 			}
 
-			b.TriggerShutdown()
-
-			err := wg.Wait()
+			err := shutdown()
 			if err == nil {
 				t.Errorf("expected error not found")
 			}
-
 			if err != errTest {
 				t.Fatalf("unexpected error found: %v", err)
 			}